Hello all!
I drive a 1994 850 Turbo. 158,000 miles.

Several months back, due to losing coolant through a leaky heater core, I decided to bypass the heater and connect the two pipes that went into the firewall. As far as I can tell, I'm not losing any coolant anymore. But after driving for a while, my engine smells like something burning. Especially when the car has been idle for a while.

I know I have a slight oil leak- could it just be due to the oil leak?
Is it possible that my engine could smell like this without it actually overheating?

Also, a side note: my temperature gauge on the dash never gets above the mid-way point. When I'm driving steadily or on the highway, it's actually below the mid-point. When I'm idle, I can see the temperature gauge rise until it stops in the middle. When I start driving again, it drops again.

 

Its dropping because there is flow over the radiator. When your car is idling...do you ever hear the fans turn on?

 

My guess would be that you have a bad thermostat that is stuck open for the most part.

As for the smell, is it burning oil smell? That is likely the problem.

 

I'm not sure that I have. But I'll have to pay close attention now.

 

I was just idle in a drive thru, and saw steam coming from under the hood. I know I should have turned the car off, but I was just a couple blocks from home so I drove it home and looked under the hood. After the drive home I couldn't see any steam though.

 

Sounds like you need a thermostat; it should stay right around 3 PM position once it's up to operating temp.

 

From your description it sounds like you have a bad thermostat that can't close and hold the temperature up where it should be.

"Is it possible that my engine could smell like this without it actually overheating?"
Smell like something is burning ?? Sure. Because something like oil could be getting hot enough to cook and smell bad or it gets too close to the exhaust and is burning off.


That heater core is the weakest link in a Volvo. That's why the first thing I do when I get one is replace it with a wood stove.

 

Same thing with the AC. Rather have my trusty Frigidaire hanging out the window than that wimpy stock Volvo unit.

Finally made my co-workers shut up with those extension cord jokes, got me a jen a rator !!

 

I'll do the thermostat then, thanks! Another question though, what about the steam? I'll check the cooling fan, but could the steam coming from under the hood have been one of the radiator hoses? Or the reservoir cap?

 

The steam could be anything. It's one of those things you have to get your face in there and track down. It could be a puddle you hit before you pulled into that drive thru. It's likely if you're noticing the coolant level is going down a bit you have a leak and there are plenty of locations it could be coming from.

In the back on the passenger side there is a approx 3/8" X 3" rubber line (turbo only) that connects to metal lines that feed coolant to the turbo. Under the distributor cap is where the two heater hoses go and that area is really hard to see well because there is so much stuff in the way unless you pull the air cleaner housing. It's also the place to check the lower radiator hose connection. I had a leak, turned out to be the lower hose connection in that area and after fixing that I found one of the heater hoses bad too. Check all the seams on the radiator and then the thermostat housing.

Clean piece of cardboard under the car at night might show you where you have a leak or give you some peace of mind it isn't leaking or it isn't leaking much.

 

Looks like I'll be doing some investigation then. Thanks for your help!

 

If you want instructions on where to cut the hole in your roof to do that heater upgrade of mine just let me know